In ventilation systems, as they are being used in aircraft, for example, a low frequency high volume noise is generated at joints between air ducts, due to the redirection of the air flow when transitioning from one air duct to another. The air flow velocity in certain air ducts, the so called riser ducts is typically very high. When this airflow is redirected into transversal air ducts, this air flow should be re directed to both sides of the transversal air duct. The distribution in both directions can be different and also 100% in one direction, for example. The turbulences generated at the joint of the air ducts are a significant source of low frequency noise. This noise can actually not be reduced through the use of conventional mufflers. In particular in the cabin of an aircraft with a ventilation system, such noise impairs the comfort of the passengers in the cabin.
In view of the foregoing, there may be a need to provide an air distributor, which avoids the generation of disturbing noise due to the redirection of an air flow, in particular reducing the disturbing noise generated by low frequency noise. In addition, other needs desirable features, and characteristics will become apparent from the subsequent summary and detailed description and the appended claims, taken in conjunction with the accompanying drawings and this background.